Methods and compositions for the inhibition of meristematic growth on cucurbit rootstock

ABSTRACT

The invention provides methods of inhibiting the growth of a shoot apical meristem of a cucurbit rootstock plant, comprising contacting a shoot apical meristem of the cucurbit rootstock plant with an effective amount of a composition comprising one or more fatty alcohols, thereby inhibiting the growth of the shoot apical meristem of the cucurbit rootstock plant. The present invention further provides methods for preparing and producing cucurbit rootstock plants for grafting and methods for grafting. Additionally provided are cucurbit rootstock plants and plant parts and grafted cucurbit plants produced by the methods of the invention.

STATEMENT OF PRIORITY

This application claims the benefit, under 35 U.S.C. §119 (e), of U.S.Provisional Application No. 61/647,312, filed May 15, 2012, the entirecontents of which is incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to compositions and methods for inhibitingthe shoot apical meristem of cucurbit rootstock plants.

BACKGROUND OF THE INVENTION

Cultivated crops in the plant family Cucurbitaceae such as watermelon,squash, cucumber and melon have been using grafted plants for commercialproduction in many production areas. This is done to overcome problemsrelated to soil borne pathogens, abiotic stress and for improvement inyield and fruit quality, and for extension of the growing season.Consequently, there is a strong demand in many parts of the world forgrafted cucurbit plants, including Asia, Europe, the United States ofAmerica and Mexico. However, grafting cucurbits is a labor intensiveprocess which requires a skilled, efficient, and consistent labor force.The cost and quality of grafted plants are key input cost forproduction.

Typically, the rootstock varieties (Lagenaria spp., interspecific squashhybrids, wax gourds or wild watermelon) used in grafting produce muchmore vigorous plants than scion plants, and thus the shoot growth of therootstock on grafted plant can outcompete the scion for light, water andnutrients. Consequently, the standard practice is to remove by hand theshoot tip of rootstock in the seedling tray before grafting and againbefore grafts leave the transplant house. The grower then needs to scoutfields and further hand prune rootstock shoot growth in the field for aperiod of time to eliminate any shoots of the rootstock plants that weremissed or have regrown. Failure to remove rootstock shoots can adverselyaffect the development of grafts in transplant production, theestablishment of grafted plants in the field, and the productivity ofgrafted plants due to the competition by the vigorous rootstock shootsthat remain and are allowed to grow.

This repeated pruning can represent a significant labor need and expenseto the grower and is particularly limiting in areas where labor costsare high, such as in the U.S. Currently, in Mexico, growers are able tocommercially supply grafted watermelon plants, but in the U.S., graftedcucurbit plants are not produced on a commercial scale. Phytosanitaryimport restrictions prevent the movement of soil (or seedlings in soil)from Mexico to the USA, therefore, the U.S. commercial production cannoteasily use grafted plants produced in Mexico.

The present invention overcomes the shortcomings in the field byproviding alternative methods for inhibiting the shoot apical meristemof a cucurbit rootstock plant to be used in grafting procedures.

SUMMARY OF THE INVENTION

One aspect of the present invention provides a method of inhibiting thegrowth of a shoot apical meristem of a cucurbit plant, comprisingcontacting a shoot apical meristem of the cucurbit plant with aneffective amount of a composition comprising one or more fatty alcohols,thereby inhibiting the growth of the shoot apical meristem of thecucurbit plant. In some aspects, the cucurbit plant is a cucurbitrootstock plant.

In other aspects, the present invention provides a method of producing acucurbit rootstock plant for grafting, comprising contacting a shootapical meristem of a cucurbit rootstock plant with an effective amountof a composition comprising one or more fatty alcohols prior tografting, thereby inhibiting the growth of the shoot apical meristem ofthe cucurbit rootstock plant and producing a cucurbit rootstock plantfor grafting.

A further aspect of the invention provides a method of producing agrafted cucurbit plant, comprising (a) contacting a shoot apicalmeristem of a cucurbit rootstock plant with an effective amount of acomposition comprising one or more fatty alcohols; and (b) grafting acucurbit scion onto the cucurbit rootstock plant of (a), therebyproducing a grafted cucurbit plant.

A further aspect of the invention provides a method of increasing theamount of at least one nonstructural carbohydrate in a cucurbit plant,comprising contacting a shoot apical meristem of the cucurbit plant withan effective amount of a composition comprising one or more fattyalcohols, thereby inhibiting the growth of the shoot apical meristem andincreasing the amount of at least one nonstructural carbohydrate in thecucurbit plant. In some aspects, the cucurbit plant is a cucurbitrootstock plant. In other embodiments, the at least one nonstructuralcarbohydrate comprises total nonstructural carbohydrates.

The present invention further provides a method of grafting a cucurbitscion onto a cucurbit rootstock plant, comprising contacting a shootapical meristem of a cucurbit rootstock plant with an effective amountof a composition comprising one or more fatty alcohols; and (b) graftinga cucurbit scion onto the cucurbit rootstock plant of (a).

In other aspects, the present invention provides a method of increasinggrafting success rate between a cucurbit rootstock plant and a cucurbitscion plant, comprising (a) inhibiting the growth of a shoot apicalmeristem of the cucurbit rootstock plant by contacting a shoot apicalmeristem of the cucurbit rootstock plant with an effective amount of acomposition comprising one or more fatty alcohols prior to grafting; and(c) grafting a cucurbit scion onto the cucurbit rootstock plant of (a),wherein the grafting success rate of the rootstock to the scion isincreased.

In still other aspects of the invention, the composition comprising oneor more fatty alcohol comprises N-hexanol (C₆) fatty alcohol, N-heptanol(C₇) fatty alcohol, N-octanol (C₈) fatty alcohol, N-nonanol (C₉) fattyalcohol, N-decanol (C₁₀) fatty alcohol, N-undecanol (C₁₁) fatty alcohol,N-dodecanol (C₁₂), N-tridecanol (C₁₃) fatty alcohol, N-tetradecanol(C₁₄) fatty alcohol, N-pentadecanol (C₁₅) fatty alcohol, N-hexadecanol(C₁₆) fatty alcohol, N-heptadecanol (C₁₇) fatty alcohol, N-octadecanol(C₁₈) fatty alcohol, N-nonadecanol (C₁₉) fatty alcohol, N-eicosanol(C₂₀) fatty alcohol, and/or any combination thereof. In other aspects ofthe invention, the composition comprising one or more fatty alcoholcomprises N-hexanol fatty alcohol (C₆), N-octanol (C₈) fatty alcohol,N-decanol (C₁₀) fatty alcohol, N-dodecanol (C₁₂), N-tetradecanol, or anycombination thereof. In further aspects of the invention, thecomposition comprising one or more fatty alcohols comprises N-octanol(C₈) fatty alcohol, N-decanol (C₁₀) fatty alcohol, or a combinationthereof. In still further aspects of the invention, the concentration ofthe one or more fatty alcohols in the composition can be about 2.0%(v/v) to about 40% (v/v).

In further aspects of the invention, the cucurbit rootstock plant is awild watermelon rootstock plant, a bottle gourd rootstock plant,Lagenaria siceraria, an interspecific squash rootstock plant, figleafgourd, wax gourd, C. moschata, Cucumis hystrix Chakrav. Cucumis hytivusJ. F. Chen & J. H. Kirkbr., Cucumis metuliferus E. Mey. ex Naud.,Cucumis melo, and/or other suitable wild-type cucurbit.

The present invention further provides cucurbit rootstock plants andplant parts and grafted cucurbit plants produced using the methodsdescribed herein

The foregoing and other aspects of the present invention will now bedescribed in more detail with respect to other embodiments describedherein. It should be appreciated that the invention can be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the problem of shoot regrowth after manually removing theshoot apical meristem in a cucurbit rootstock plant.

FIG. 2 shows the growing point of the cucurbit rootstock plant.

FIG. 3 shows the mean hypocotyl fresh weight for the ‘Carnivor’interspecific hybrid squash and ‘Emphasis’ bottle gourd rootstockseedlings following treatment with the fatty alcohol.

FIG. 4 shows the hypocotyl dry weights for the ‘Carnivor’ interspecifichybrid squash and ‘Emphasis’ bottle gourd rootstock seedlings followingtreatment with the fatty alcohol.

FIG. 5 shows the mean hypocotyl length for the ‘Carnivor’ interspecifichybrid squash and ‘Emphasis’ bottle gourd rootstock seedlings followingtreatment with the fatty alcohol.

FIG. 6 shows the mean hypocotyl width for the ‘Carnivor’ interspecifichybrid squash and ‘Emphasis’ bottle gourd rootstock seedlings followingtreatment with the fatty alcohol.

FIG. 7 shows the mean cotyledon fresh weight for the ‘Carnivor’interspecific hybrid squash and ‘Emphasis’ bottle gourd rootstockseedlings following treatment with the fatty alcohol.

FIG. 8 shows the mean cotyledon dry weight for the ‘Carnivor’interspecific hybrid squash and ‘Emphasis’ bottle gourd rootstockseedlings following treatment with the fatty alcohol.

FIG. 9 shows the mean cotyledon length for the ‘Carnivor’ interspecifichybrid squash and ‘Emphasis’ bottle gourd rootstock seedlings followingtreatment with the fatty alcohol.

FIG. 10 shows the mean cotyledon width for the ‘Carnivor’ interspecifichybrid squash and ‘Emphasis’ bottle gourd rootstock seedlings followingtreatment with the fatty alcohol.

FIG. 11 shows the cotyledon area for the ‘Carnivor’ interspecific hybridsquash and ‘Emphasis’ bottle gourd rootstock seedlings followingtreatment with the fatty alcohol.

FIG. 12 shows a cotyledon thickness estimate for the ‘Carnivor’interspecific hybrid squash and ‘Emphasis’ bottle gourd rootstockseedlings following treatment with the fatty alcohol.

FIG. 13 shows the amount of ethanol (EtOH) soluble carbohydrates for the‘Carnivor’ interspecific hybrid squash and ‘Emphasis’ bottle gourdrootstock seedlings following treatment with the fatty alcohol.

FIG. 14 shows the starch content for the ‘Carnivor’ interspecific hybridsquash and ‘Emphasis’ bottle gourd rootstock seedlings followingtreatment with the fatty alcohol.

FIG. 15 shows the mean total nonstructural carbohydrates for the‘Carnivor’ interspecific hybrid squash and ‘Emphasis’ bottle gourdrootstock seedlings following treatment with the fatty alcohol.

DETAILED DESCRIPTION OF THE INVENTION

Unless the context indicates otherwise, it is specifically intended thatthe various features of the invention described herein can be used inany combination.

Moreover, the present invention also contemplates that in someembodiments of the invention, any feature or combination of features setforth herein can be excluded or omitted. To illustrate, if thespecification states that a composition comprises components A, B and C,it is specifically intended that any of A, B or C, or a combinationthereof, can be omitted and disclaimed singularly or in any combination.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. The terminology used in thedescription of the invention herein is for the purpose of describingparticular embodiments only and is not intended to be limiting of theinvention.

As used in the description of the invention and the appended claims, thesingular forms “a,” “an” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise.

As used herein, “and/or” refers to and encompasses any and all possiblecombinations of one or more of the associated listed items, as well asthe lack of combinations when interpreted in the alternative (“or”).

The term “about,” as used herein when referring to a measurable valuesuch as a dosage, an amount or a time period and the like, is meant toencompass variations of ±20%, ±10%, ±5%, ±1%, ±0.5%, or even ±0.1% ofthe specified amount (e.g., an amount of one or more fatty alcohol).

As used herein, phrases such as “between X and Y” and “between about Xand Y” should be interpreted to include X and Y. As used herein, phrasessuch as “between about X and Y” mean “between about X and about Y.” Asused herein, phrases such as “from about X to Y” mean “from about X toabout Y.”

The term “comprise,” “comprises” and “comprising” as used herein,specify the presence of the stated features, integers, steps,operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, integers, steps,operations, elements, components, and/or groups thereof.

As used herein, the transitional phrase “consisting essentially of”means that the scope of a claim is to be interpreted to encompass thespecified materials or steps recited in the claim and those that do notmaterially affect the basic and novel characteristic(s) of the claimedinvention. Thus, the term “consisting essentially of” when used in aclaim of this invention is not intended to be interpreted to beequivalent to “comprising.”

As used herein, the phrase “inhibit the shoot apical meristem” or“inhibiting the shoot apical meristem” and grammatical variationsthereof, refers to reducing the growth of the shoot apical meristem byburning, desiccating, destroying, removing and/or killing the shootapical meristem.

As used herein, the terms “inhibit,” “inhibits,” “inhibited,”“inhibition” and similar terms used in reference to the growth of theshoot apical meristem mean a decrease or reduction in growth of theshoot apical meristem of at least about 20%, 25%, 30%, 35%, 40%, 45%,50%, 55%, 60%, 75%, 80%, 85%, 90%, 95%, 100% as compared to a control(e.g., a rootstock plant that has not been treated with a compositioncomprising one or more fatty alcohols). In particular embodiments, theinhibition results in no or essentially no (i.e., an insignificantamount, e.g., less than about 10%, less than about 5% or even less thanabout 1%) detectable growth of the shoot apical meristem.

Current practices of preparing cucurbit rootstock incur significantlabor costs due to the need to hand prune rootstock shoot growth. Handpruning is not only time consuming but often ineffective due to regrowthof the apical shoot (See, FIG. 1). Thus, using manual methods, thepruning must be done prior to grafting and then again in the field toagain eliminate any shoots of the rootstock that were missed or regrowafter grafting. Typically, the rootstock plants are quite vigorous incomparison to the scion plants and as a result, if rootstock shoots arenot removed, their relatively greater vigor can adversely affect thedevelopment of grafts in transplant production, the establishment ofgrafted plants in field, and the productivity of grafted plants. Thepresent invention provides an economical alternative to hand pruning ofa cucurbit shoot apical meristem by providing a chemical means ofeliminating the cucurbit rootstock shoot apical meristem.

The methods of the present invention for removing a cucurbit meristemare more effective than previous methods because the methods of theinvention using fatty alcohol can result in complete removal of themeristem without damage to the hypocotyl. Other methods such as manualremoval of the meristem (cutting) or other chemicals are either notcomplete (only a single cell left behind allows for regrowth) or damagethe rootstock too much for it to survive and be useful in grafting.

Thus, in one aspect, the present invention provides a method ofinhibiting the growth of a shoot apical meristem of a cucurbit plant,comprising contacting a shoot apical meristem (See, for example, FIG. 2)of the cucurbit plant with an effective amount of a compositioncomprising, consisting essentially of, or consisting of one or morefatty alcohols, thereby inhibiting the growth of the shoot apicalmeristem of the cucurbit plant. In some embodiments, the contacting canbe done before and/or after grafting. In other embodiments, the cucurbitplant is a cucurbit rootstock plant.

In a further aspect, the present invention provides a method ofpreparing a cucurbit rootstock plant for grafting, comprising contactinga shoot apical meristem of a cucurbit rootstock plant with an effectiveamount of a composition comprising, consisting essentially of, orconsisting of one or more fatty alcohols, thereby inhibiting the growthof the shoot apical meristem of the cucurbit rootstock plant, whereininhibition of the shoot apical meristem prepares the rootstock forgrafting.

In an additional aspect, the present invention provides a method ofproducing a cucurbit rootstock plant for grafting, comprising contactinga shoot apical meristem of a cucurbit rootstock plant with an effectiveamount of a composition comprising, consisting essentially of, orconsisting of one or more fatty alcohols, thereby inhibiting the growthof the shoot apical meristem of the cucurbit rootstock plant andproducing a cucurbit rootstock plant for grafting.

A further aspect of the present invention provides a method of producinga grafted cucurbit plant, comprising (a) preparing a cucurbit rootstockplant for grafting by contacting a shoot apical meristem of the cucurbitrootstock plant with an effective amount of a composition comprising,consisting essentially of, or consisting of one or more fatty alcoholsprior to grafting; and (b) grafting a cucurbit scion onto the cucurbitrootstock plant of (a), thereby producing a grafted cucurbit plant.

In some aspects, a method of increasing the amount of at least onenonstructural carbohydrate in a cucurbit rootstock plant, comprisingcontacting a shoot apical meristem of the cucurbit rootstock plant withan effective amount of a composition comprising one or more fattyalcohols, thereby inhibiting the growth of the shoot apical meristem andincreasing the amount of at least one nonstructural carbohydrate in thecucurbit rootstock plant. In some embodiments, the at least onenonstructural carbohydrate can comprise total nonstructuralcarbohydrates.

A further aspect of the invention provides a method of grafting acucurbit scion onto a cucurbit rootstock plant, comprising (a)inhibiting the growth of a shoot apical meristem of the cucurbitrootstock plant by contacting a shoot apical meristem of the cucurbitrootstock plant with an effective amount of a composition comprising oneor more fatty alcohols prior to grafting; and (b) grafting a cucurbitscion onto the cucurbit rootstock plant of (a).

In other aspects, the present invention provides a method of increasinggrafting successor grafting success rate between a cucurbit rootstockplant and a cucurbit scion plant, comprising (a) inhibiting the growthof a shoot apical meristem of the cucurbit rootstock plant with aneffective amount of a composition comprising one or more fatty alcohols;and (b) grafting a cucurbit scion onto the cucurbit rootstock plant of(a), wherein the grafting success or grafting success rate of therootstock to the scion is increased as compared to a control in whichgrowth of a shoot apical meristem of the cucurbit rootstock plant is notinhibited.

The terms “increase,” “increasing,” “increased,” “enhance,” “enhanced,”“enhancing,” and “enhancement” (and grammatical variations thereof), asused herein, describe an increase in the amount of at least onenonstructural carbohydrates in a cucurbit rootstock plant of at leastabout 1 fold to about 1000 fold (or about 0.1 μg to about 10 μgnonstructural carbohydrate) per hypocotyl and/or cotyledon and/or aincrease in grafting success rate between a cucurbit rootstock plant anda cucurbit scion plant of at least about 5% to about 100% as compared toa control. Thus, in some embodiments, an increase in the amount of atleast one nonstructural carbohydrate can be observed in a cucurbitrootstock plant prepared or produced using the methods of the inventionby comparison to the amount in a control cucurbit rootstock plant. Acontrol cucurbit rootstock plant can be an untreated cucurbit rootstockplant (e.g., a cucurbit rootstock plant not produced or prepared usingthe methods of this invention), and/or a cucurbit rootstock plantproduced using the methods of the invention on day one of contact with acomposition of fatty alcohols as described herein.

In other embodiments, grafting success between a cucurbit rootstockplant prepared or produced using the methods of the invention and ascion can be measured by comparison to the grafting success of a controlcucurbit rootstock plant and a cucurbit scion plant. A control cucurbitrootstock plant can be a cucurbit rootstock plant that has not beenprepared or produced using the methods of this invention. In someembodiments, grafting success can be observed between an individualgrafted scion and rootstock plant as compared to a control rootstockplant grafted to a scion and/or grafting success can be as compared to apopulation of control grafted plants. Grafting success can be measuredusing factors that include, but are not limited to, the percentage ofgrafts that have healed (e.g., whether the graft can be pulled apart)and/or the amount of root regrowth.

Thus, in some embodiments, an increase in the amount of at least onenonstructural carbohydrate in a cucurbit rootstock plant can be about a1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56,57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92,93, 94, 95, 96, 97, 98, 99, 100, 125, 150, 175, 200, 225, 250, 275, 300,325, 350, 375, 400, 425, 450, 475, 500, 525, 550, 575, 600, 625, 650,675, 700, 725, 750, 775, 800, 825, 850, 875, 900, 925, 950, 975, 1000fold increase, and the like, or any range therein, in the amount of atleast one nonstructural carbohydrate per hypocotyl and/or cotyledon of arootstock plant as compared to a control. In some embodiments, theincrease in the amount of at least one nonstructural carbohydrate can befrom about 3 fold to about 550 fold. In other embodiments, the increasein the amount of at least one nonstructural carbohydrates can be fromabout 5 fold to about 30 fold, and the like.

In other embodiments, an increase in the amount of at least onenonstructural carbohydrate in a cucurbit rootstock plant can be about0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5,1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3,3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5,4.6, 4.7, 4.8, 4.9, 5, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6,6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, 7, 7.1, 7.2, 7.3, 7.4, 7.5,7.6, 7.7, 7.8, 7.9, 8, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9,9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 10 μg, and the like, or anyrange therein, in the amount of the at least one nonstructuralcarbohydrate per hypocotyl and/or cotyledon of a rootstock plant ascompared to a control.

In still other embodiments, an increase in grafting success (rate)between a cucurbit rootstock plant and a cucurbit scion plant can be apercent increase in grafting success of at least about 5%, 6%, 7%, 8%,9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%,23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%,37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%,51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%,65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%,79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%,93%, 94%, 95%, 96%, 97%, 98%, 99%, 100%, and the like, or any rangetherein, as compared to a control. In some particular embodiments, anincrease in grafting success between a cucurbit rootstock plant and acucurbit scion plant can be at least about 25% to about 90%, or about45% to about 85% increase in grafting success as compared to a control.In other embodiments, the grafting success is increased by about 50% ascompared to a control. In still other embodiments, the grafting successis increased by about 80% as compared to a control.

As used herein, a successful graft refers to a graft between a rootstockplant and a scion plant that is healed and viable and/or root regrowthis observed. In some embodiments, a successful graft can be measuredafter a period of time following first grafting. In particularembodiments, the time period can be from about 5 to about 14 days (i.e.,about 5, 6, 7, 8, 9, 10, 11, 12, 13, or 14 days) after first grafting.

As used herein, “grafting success” or “grafting success rate” ismeasured as the number of grafts that are healed and viable after aperiod time following first grafting as compared to the number that arenot healed and viable after said time period. In some embodiments, thetime period can be about from about 5 to about 10 days (i.e., about 5,6, 7, 8, 9, or 10 days) after first grafting. In other embodiments, thetime period can be from about 7 to about 10 days (e.g., 7, 8, 9, 10days) after first grafting.

In additional embodiments, prior to grafting a rootstock plant havingthe growth of its shoot apical meristem inhibited as described hereincan have one or all of the cotyledons removed. Previous to the presentinvention, it was believed that a hypocotyl cannot be viably graftedwithout cotyledons. Without wishing to be bound by any particulartheory, it is hypothesize that grafting failure in the absence of thecotyledons was due to the need for the energy for graft healing; theenergy being provided by the photosynthesis of the cotyledons. However,the removal of the meristem using the fatty alcohol treatment asdescribed herein, as well as time following the application to allow thehypocotyl time to store carbohydrates, makes grafting without one orboth cotyledons possible. The advantages of removing cotyledons prior tografting include complete control of regrowth because of removal ofmeristem; more grafted plants can be placed in a tray (improvedefficiency of grafting); and decreased disease probability in thehealing chamber as there is less area for pooling of condensation.

As used herein, the term “nonstructural carbohydrate” refers to anycarbohydrate that can be made available to the plant for energy use ingraft healing. Thus, these are carbohydrates that are easily convertedback into glucose and metabolized. Nonlimiting examples of nonstructuralcarbohydrates include glucose, sucrose, fructose, fructan, and starch.Methods for detecting nonstructural carbohydrates are known in the art(See, e.g., Zhao et al. (Crop Science 50:1537-1545 (2010)). The term“total nonstructural carbohydrate” is used herein when discussing as agroup the nonstructural carbohydrates that were analyzed.

In some embodiments, contact of the composition comprising the fattyalcohols with the shoot apical meristem can be for about 1 hour to about24 hours. In some particular embodiments, the contact of the compositioncomprising the fatty alcohols with the shoot apical meristem can be forabout 1 hour to about 12 hours. In still other embodiments, contact ofthe composition comprising the fatty alcohols with the shoot apicalmeristem can be for about 1 hour to about 6 hours. Thus, contact of thecomposition comprising the fatty alcohols with the shoot apical meristemcan be for about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,17, 18, 19, 20, 21, 22, 23, 24 hours and the like or any range therein.

In some embodiments, following contact of the shoot apical meristem withthe composition, the cucurbit plant can be incubated to allow time forthe composition to kill the meristem and the plant rest prior tografting to a scion. Thus, “incubate,” “incubating,” and “incubation”(and grammatical variations thereof) refer to the time between thecontacting and when the rootstock can be used for grating to a scion(e.g., the time for the composition to inhibit/kill the rootstock apicalmeristem and for the treated plant to rest/recover before grafting tothe scion). In representative embodiments, “incubating” can be for atime of about 4 hours to about 21 days after initial contact of theshoot apical meristem of the rootstock plant with the compositioncomprising the fatty alcohols. In some embodiments, the shoot apicalmeristem of rootstock plant is incubated for about 1 day to about 21days following contact of the shoot apical meristem with saidcomposition. In an additional embodiment, the shoot apical meristem canbe incubated for about 5 to about 14 days after contact of the shootapical meristem with said composition. In other embodiments, the shootapical meristem of rootstock plant is incubated for about 5 to about 10days after contact of the shoot apical meristem with said composition.In still other embodiments, the shoot apical meristem of rootstock plantis incubated for about 5 to about 7 days after contact of the shootapical meristem with said composition.

Thus, in some embodiments of the invention, the shoot apical meristem ofrootstock plant is incubated following contact with the composition offatty alcohols for about 4 hours, about 5 hours, about 6 hours, about 7hours, about 8 hours, about 9 hours, about 10 hours, about 11 hours,about 12 hours, about 13 hours, about 14 hours, about 15 hours, about 16hours, about 17 hours, about 18 hours, about 19 hours, about 20 hours,about 21 hours, about 22 hours, about 23 hours, about 24 hours, about 1day, about 2 days, about 3 days, about 4 days, about 5 days, about 6days, about 7 days, about 8 days, about 9 days, about 10 days, about 11days, about 12 days, about 13 days, about 14 days, about 15 days, about16 days, about 17 days, about 18 days, about 19 days, about 20 days, orabout 21 days.

Accordingly, in representative embodiments, a cucurbit scion can begrafted to a rootstock plant contacted with the fatty alcoholcompositions as described herein at about 4 hours to about 21 days afterfirst contacting the shoot apical meristem of said rootstock plant witha composition comprising one or more fatty alcohols. In some embodimentsof the invention, a cucurbit scion can be grafted to a rootstock plantcontacted with the fatty alcohol compositions as described herein atabout 1 day to about 21 days after first contacting the shoot apicalmeristem of said rootstock plant with a composition comprising one ormore fatty alcohols. In other embodiments, a cucurbit scion can begrafted to a rootstock plant contacted with the fatty alcoholcompositions as described herein at about 5 days to about 7 days afterfirst contacting the shoot apical meristem of said rootstock plant witha composition comprising one or more fatty alcohols.

Thus, in some embodiments of the invention, a cucurbit scion can begrafted to a rootstock plant contacted with the fatty alcoholcompositions as described herein at about 4 hours, about 5 hours, about6 hours, about 7 hours, about 8 hours, about 9 hours, about 10 hours,about 11 hours, about 12 hours, about 13 hours, about 14 hours, about 15hours, about 16 hours, about 17 hours, about 18 hours, about 19 hours,about 20 hours, about 21 hours, about 22 hours, about 23 hours, about 24hours, about 1 day, about 2 days, about 3 days, about 4 days, about 5days, about 6 days, about 7 days, about 8 days, about 9 days, about 10days, about 11 days, about 12 days, about 13 days, about 14 days, about15 days, about 16 days, about 17 days, about 18 days, about 19 days,about 20 days, or about 21 days after initial contact of the shootapical meristem of said rootstock plant with said composition.

Any suitable cucurbit rootstock plant can be used with this invention.Non-limiting examples of a cucurbit rootstock plant include a wildwatermelon rootstock plant (Citrullus lanatus subsp. lanatus, Citrulluslanatus subsp. mucosospermus), a bottle gourd rootstock plant (e.g.,Lagenaria spp., Lagenaria siceraria), an interspecific squash rootstockplant (e.g., Cucurbita maxima×Cucurbita moschata), a figleaf gourd(e.g., Cucurbita ficifolia) plant, wax gourd (Benincasa hispida) plant,a C. moschata plant, a Cucumis hystrix Chakrav plant, a Cucumis hytivusJ. F. Chen & J. H. Kirkbr. plant, a Cucumis metuliferus E. Mey. ex Naud.plant, a Cucumis melo plant, and/or other wild-type cucurbit plant(e.g., C. lanatus, Citrulus lanatus subsp lanatus ‘Ojakkyo’; Cucumisafricanus; Cucumis myriocarpus).

Additionally, any cucurbit scion plant suitable for use with a cucurbitrootstock plant described herein can be used with this invention. Thus,in some embodiments, a cucurbit scion plant includes, but is not limitedto, a watermelon (Citrullus lanatus subsp. vulgaris) scion, a melonscion (Cucumis melo), an oriental melon scion (Cucumis melo var. makuwa)or a cucumber scion (Cucumis sativus).

Thus, in representative embodiments the present invention provides abottle gourd rootstock plant and a watermelon (Citrullus lanatus) scion.In other embodiments, the present invention provides an interspecificsquash rootstock plant and watermelon scion (Citrullus lanatus), a melonscion (Cucumis melo), an oriental melon scion (Cucumis melo var. makuwa)or a cucumber scion (Cucumis sativus). In further embodiments, thepresent invention provides a figleaf gourd rootstock plant (Cucurbitaficifolia) and a cucumber scion. In still further embodiments, thepresent invention provides a Cucurbita moschata rootstock plant and acucumber scion or a watermelon scion. In some embodiments of theinvention, the cucurbit rootstock plant is wild watermelon (Citrulluslanatus subsp. lanatus, Citrullus lanatus subsp. mucosospermus,Citrullus colocynthis) and the scion is a watermelon plant (Citrulluslanatus subsp vulgaris). In other embodiments, the present inventionprovides a Cucumis melo rootstock plant and a melon scion. In stillother embodiments, the cucurbit rootstock plant is a wax gourd(Benincasa hispida) plant and the scion is a watermelon plant.

Any suitable method of contacting the fatty alcohol composition to thecucurbit rootstock shoot apical meristem can be used with the methods ofthis invention, wherein growth of the shoot apical meristem is inhibitedbut optionally in which the cotyledons remain substantially intact andcan support the growth of a grafted scion plant. Accordingly,non-limiting methods of contacting the fatty alcohol composition to thecucurbit rootstock shoot apical meristem include applying droplets tothe shoot apical meristem of the seedling, “painting” the solution ontocucurbit rootstock shoot apical meristem, spraying or misting therootstock plants with the fatty alcohol composition such that thecomposition drips down into the shoot apical meristem, and/or dippingcucurbit rootstock seedlings in a fatty alcohol composition, wherein thecomposition drips down into the shoot apical meristem when the plant isuprighted after dipping. It is noted that the cotyledons of cucurbitrootstock plants are waxy and therefore, hydrophobic. Further, somespecies of rootstock plants have trichomes on the epidermis that reducesabsorption of the fatty alcohol composition. As such, a fatty alcoholcomposition applied to a cucurbit rootstock plant will roll off thecotyledons toward the shoot apex, coming to rest on the shoot apicalmeristem area, leaving the cotyledons with little or no damaged butburning or killing the shoot apical meristem. In some representativeembodiments, the cotyledons of the rootstock plant are partially orfully removed. Thus, in some embodiments, the rootstock plant has onecotyledon remaining. In other embodiments, the rootstock plant has nocotyledons remaining.

Thus, in representative embodiments, contacting the compositioncomprising, consisting essentially of, or consisting of one or morefatty alcohols to a shoot apical meristem of a cucurbit rootstock plantcomprises applying one or more droplets of the composition comprising,consisting essentially of, or consisting of one or more fatty alcoholsto the shoot apical meristem of the rootstock plant. In some embodimentsof the invention, a droplet can be a volume of about 0.25 μl to about500 μl, or any range therein. In other embodiments, a droplet can be avolume of about 1 μl to about 250 μl, or any range therein. In stillother embodiments, a droplet can be a volume of about 5 μl to about 50μl, or any range therein. Accordingly, in some embodiments, a dropletcan be a volume of about 0.25 μl about 0.5 μl, about 0.75 μl, about 1μl, about 2 μl about 3 μl, about 4 μl, about 5 μl, about 6 μl, about 7μl, about 8 μl, about 9 μl, about 10 μl, about 11 μl, about 12 μl, about13 μl, about 14 μl, about 15 μl, about 16 μl, about 17 μl, about 18 μl,about 19 μl, about 20 μl, about 25 μl, about 30 μl, about 35 μl, about40 μl, about 45 μl, about 50 μl, about 55 μl, about 60 μl, about 65 μl,about 70 μl, about 75 μl, about 80 μl, about 85 μl, about 90 μl, about95 μl, about 100 μl, about 125 μl, about 150 μl, about 175 μl, about 200μl, about 225 μl, about 250 μl, about 275 μl, about 300 μl, about 325μl, about 350 μl, about 375 μl, about 400 μl, about 425 μl about 450 μl,about 475 μl, and/or about 500 μl, and the like. In particularembodiments, the droplet can be about 20 μl.

In representative embodiments, the total concentration of the one ormore fatty alcohols in the composition that is contacted (as a droplet,paint, spray, mist, and the like) with the shoot apical meristem can beabout 2.0% (volume/volume (v/v)) to about 40% (v/v) fatty alcohol, andany range therein. In other embodiments, the range of the concentrationof the one or more fatty alcohols in the composition can be about 2.0%(v/v) to about 30% (v/v) fatty alcohol, about 2.0% (v/v) to about 20%(v/v) fatty alcohol, about 3.0% (v/v) to about 5% (v/v) fatty alcohol.Thus in some embodiments, the concentration of one or more fattyalcohols in the composition that is contacted with the shoot apicalmeristem of the cucurbit root stock can be about 2.0%, 2.5%, 3.0%, 3.5%,4.0%, 4.5%, 5.0%, 5.5%, 6.0%, 6.5%, 7.0%, 7.5%, 8.0%, 8.5%, 9.0%, 9.5%,10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13.0%, 13.5%, 14.0%, 14.5%, 15.0%,15.5%, 16.0%, 16.5%, 17.0%, 17.5%, 18.0%, 18.5%, 19.0%, 19.5%, 20%,20.5%, 21%, 21.5%, 22%, 22.5%, 23.0%, 23.5%, 24.0%, 24.5%, 25.0%, 25.5%,26.0%, 26.5%, 27.0%, 27.5%, 28.0%, 28.5%, 29.0%, 29.5%, 30%, 30.5%, 31%,31.5%, 32%, 32.5%, 33.0%, 33.5%, 34.0%, 34.5%, 35.0%, 35.5%, 36.0%,36.5%, 37.0%, 37.5%, 38.0%, 38.5%, 39.0%, 39.5%, 40% (volume/volume),and the like, or any combination thereof.

In representative embodiments, the general structure of a fatty alcoholis

, wherein n=number of carbons. In some embodiments of the invention, n=6to 20. In other embodiments of the invention, n=6 to 12. In someembodiments, the one or more fatty alcohols can be one or more saturatedfatty alcohols, unsaturated fatty alcohols, or a combination thereof. Inparticular embodiments, the one or more fatty alcohols can be one ormore saturated fatty alcohols.

In some embodiments, the composition comprising, consisting essentiallyor, consisting of one or more fatty alcohols, comprises, consistsessentially of, or consists of N-hexanol fatty alcohol (C₆), N-heptanol(C₇) fatty alcohol, N-octanol (C₈) fatty alcohol, N-nonanol (C₉) fattyalcohol, N-decanol (C₁₀) fatty alcohol, N-undecanol (C₁₁) fatty alcohol,N-dodecanol (C₁₂), N-tridecanol (C₁₃) fatty alcohol, N-tetradecanol(C₁₄) fatty alcohol, N-pentadecanol (C₁₅) fatty alcohol, N-hexadecanol(C₁₆) fatty alcohol, N-heptadecanol (C₁₇) fatty alcohol, N-octadecanol(C₁₈) fatty alcohol, N-nonadecanol (C₁₉) fatty alcohol, N-eicosanol(C₂₀) fatty alcohol, and/or any combination thereof. In furtherembodiments, the composition comprising, consisting essentially or,consisting of one or more fatty alcohols, comprises, consistsessentially of, or consists of N-hexanol (C₆) fatty alcohol, N-octanol(C₈) fatty alcohol, N-decanol (C₁₀) fatty alcohol and N-dodecanol (C₁₂)fatty alcohol. In still further embodiments, the composition comprising,consisting essentially or, consisting of one or more fatty alcohols,comprises, consists essentially of, or consists of N-octanol (C₈) fattyalcohol and N-decanol (C₁₀) fatty alcohol. In other embodiments, thecomposition comprising, consisting essentially or, consisting of one ormore fatty alcohols, comprises, consists essentially of, or consists ofN-decanol (C₁₀) fatty alcohol. In additional embodiments, thecomposition comprising, consisting essentially or, consisting of one ormore fatty alcohols, comprises, consists essentially of, or consists ofN-octanol (C₈) fatty alcohol. In further embodiments, the fatty alcoholsuseful with the invention as described herein are saturated fattyalcohols, unsaturated fatty alcohols, or a combination thereof. In someembodiments, the individual and/or the total fatty alcohols can bepresent in the composition in the concentrations described above.

In still further embodiments, the one or more fatty alcohols in thecomposition for inhibition of the cucurbit rootstock apical meristem canbe provided by FAIR 85® (Fair Products, Inc., Cary, N.C.), Offshoot-T®(Chemtura Corp., Middlebury, Conn.), Sucker Plucker®(Drexel ChemicalCo., Memphis Tenn.), Antak® (Drexel Chemical Co., Memphis Tenn.),Royaltac® (Chemtura Corp., Middlebury, Conn.), Fairtac C-10® (FairProducts, Inc., Cary, N.C.), and the like, or any combination thereof.In some embodiments, the concentration of the one or more fatty alcoholsin a composition, wherein the fatty alcohols are provided by FAIR 85®,Offshoot-T®, Sucker Plucker®, Antak®, Royaltac®, Fairtac C-10®, orcombination thereof, can be about 2% to about 40% (v/v), about 2% (v/v)to about 30% (v/v) fatty alcohol, about 2% (v/v) to about 20% (v/v)fatty alcohol, about 3% (v/v) to about 5% (v/v), about 2% (v/v) to about6% (v/v) and/or about 3% (v/v) to about 5% (v/v) fatty alcohol asdescribed herein for fatty alcohol compositions useful for thisinvention. Thus, in some embodiments, the concentration of the one ormore fatty alcohols in a composition can be about 2%, 3%, 4%, 5%, 6%,7%, 8%, 9%, 10%, 11%, 12.0%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%,21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%,35%, 36%, 37%, 38%, 39%, 40% (v/v), and the like, and any range therein.In a representative embodiment, the concentration of the one or morefatty alcohols in a composition can be about 5.3% (v/v) (6.25% of Fair85). In other embodiments, concentration of total fatty alcohols in acomposition can be about 2.3% (v/v).

An “effective” amount of a fatty alcohol composition as used herein, isan amount of the fatty alcohol compound or composition that issufficient to achieve the intended effect, i.e., to inhibit shoot apicalmeristem growth in a cucurbit rootstock. An effective amount may varywith particular factors that are within the knowledge and expertise ofthose skilled in the art. Thus, for example, as the person skilled inthe art of grafting cucurbit plants would know, the morphologicalcharacteristics of the particular rootstock species or cultivar beingtreated can affect the amount/concentration of a fatty alcoholcomposition needed to inhibit shoot apical meristem growth in saidcucurbit rootstock plant. Such morphological characteristics include,but are not limited to, the degree of hydrophobicity of the surface ofthe cotyledons (amount of epidermal wax), the presence andquantity/concentration of epidermal hairs (trichomes) and/or themorphology of the apical meristem of the particular rootstock speciesbeing treated. An “effective amount” of the fatty alcohols for use ininhibiting shoot apical meristem growth of a cucurbit rootstock plantcan be readily determined by one of ordinary skill in the art. In someembodiments, an effective amount of a fatty alcohol compositioncomprises, consists essentially of, or consists of a total fatty alcoholconcentration about 2.0% to about 40% (v/v) as described herein, whereinthe fatty alcohol can be N-hexanol fatty alcohol (C₆), N-heptanol (C₇)fatty alcohol, N-octanol (C₈) fatty alcohol, N-nonanol (C₉) fattyalcohol, N-decanol (C₁₀) fatty alcohol, N-undecanol (C₁₁) fatty alcohol,N-dodecanol (C₁₂), N-tridecanol (C₁₃) fatty alcohol, N-tetradecanol(C₁₄) fatty alcohol, N-pentadecanol (C₁₅) fatty alcohol, N-hexadecanol(C₁₆) fatty alcohol, N-heptadecanol (C₁₇) fatty alcohol, N-octadecanol(C₁₈) fatty alcohol, N-nonadecanol (C₁₉) fatty alcohol, N-eicosanol(C₂₀) fatty alcohol, and/or any combination thereof.

In representative embodiments, the cucurbit rootstock shoot apicalmeristem is contacted with the fatty alcohol composition during the timeperiod from when the cucurbit rootstock plant's cotyledons open untilthe appearance of the first true leaf. In some embodiments, the cucurbitrootstock apical meristem is contacted with the fatty alcoholcomposition at about 5 days to about 10 days after sowing or seeding, orany range therein. Thus, in some embodiments, the shoot apical meristemis contacted with the fatty alcohol composition at about 5 days to about9 days after sowing or seeding, or about 5 days to about 7 days aftersowing or seeding. Thus, in some embodiments, the shoot apical meristemis contacted with the fatty alcohol composition at about 5 days, about 6days, about 7 days, about 8 days, about 9 days, or about 10 days and thelike, after seeding or sowing.

In some embodiments, a composition comprising one or more fatty alcoholsis contacted with the rootstock apical meristem prior to grafting.Typically, one application of the fatty alcohol composition prior tografting is sufficient to inhibit the shoot apical meristem growth ofthe rootstock plant. In other embodiments, a rootstock plant that is notcontacted with a fatty alcohol composition prior to grafting can becontacted after the grafting of the scion to the rootstock to inhibitthe shoot apical meristem of the rootstock plant post-grafting. Forexample, once the graft between the rootstock and the scion is healed,the shoot apical meristem of the rootstock can be contacted with acomposition comprising, consisting essentially of, or consisting of oneor more fatty alcohols. Accordingly, in some embodiments, the shootapical meristem of the grafted rootstock plant can be contacted with thecomposition comprising, consisting essentially of or consisting of oneor more fatty alcohols at about 5 days to about 9 days after grafting(e.g., about 5 days, about 6 days, about 7 days, about 8 days, about 9days, and the like after grafting).

In representative embodiments, a diluent or main carrier of acomposition of one or more fatty alcohols as described herein is water,and/or water comprising, for example, a surfactant (e.g., soapy water),or other agriculturally acceptable carrier. An agriculturally-acceptablecarrier can include natural or synthetic, organic or inorganic materialwhich is combined with the active component to facilitate itsapplication to the plant, or part thereof. In representativeembodiments, an agriculturally-acceptable carrier includes, but is notlimited to, inert components, dispersants, surfactants, adjuvants,tackifiers, stickers, binders, or combinations thereof, that can be usedin agricultural formulations. The concentration of agriculturallyacceptable carriers and/or inert ingredients can be about 0% to about15% of the total composition.

Accordingly, in some embodiments, the compositions comprising one ormore fatty alcohols can be mixed with one or more agriculturallyacceptable carriers and prepared by various means, e.g., byhomogeneously mixing, blending and/or grinding the composition(s) withsuitable carriers using conventional formulation techniques.

The compositions of the present invention can be made in any formulationsuitable for inhibiting a cucurbit rootstock shoot apical meristem. Suchformulations include, but are not limited to, a spray, a suspension, amist, an aerosol, a foam, paste, and combinations thereof.

In particular aspects of the present invention, compositions comprisingone or more fatty alcohols can be used in combination with additionalactive compounds. Thus, in some embodiments, compositions comprising oneor more fatty alcohols further comprise additional active compounds. Inother embodiments, the additional active compounds can be provided inone or more than one composition that is separate from the compositionscomprising one or more fatty alcohol. Additional active compounds thatare useful in combination with a composition comprising one or morefatty alcohols includes, but is not limited to, fertilizers, plantnutrients and micronutrients, amino acids, plant hormones andhormone-like compounds, pesticides, fungicides, insecticides,nematicides, reflective materials, and the like.

The present invention further provides cucurbit rootstock plants andplant parts and grafted cucurbit plants produced using the methodsdescribed herein.

The present invention is more particularly described in the followingexamples that are intended as illustrative only since numerousmodifications and variations therein will be apparent to those skilledin the art.

EXAMPLES Example 1 Inhibition of the Shoot Apical Meristem of CucurbitRootstock (Species Here)

Rootstock plants, bottle gourd (Lagenaria siceraria var. ‘Emphasis’) orinterspecific hybrid squash (C. maxima×C.moschata var. ‘Carnivor’), weresown in Fafard 3-b fertilizer-free mix and allowed to germinate. At thepoint when the cotyledons unfolded, (approx. 5-10 days after seeding) adroplet of a composition comprising fatty alcohols was applied to theshoot apical meristem of the seedling, between the cotyledons, so thatthe meristem was covered with solution. The fatty alcohol compositioncomprised a concentration of total fatty alcohols of about 2.3%(volume/volume) and was made by diluting the fatty alcohol product, FAIR85®, 1:19 or 1:24 with water. The droplet volume was 20 to 500 μl andwas applied with a pipette (20-200 μl or 1000 μl volume capability,using plastic tips). Seedlings were watered prior to treatment, to avoidneeding to water post-treatment, which can dilute or wash away the fattyalcohol solution and prevent burnout of the shoot apical meristem. Thetreated rootstock seedlings can then be grafted to the appropriate scionat about 1 to 21 days post-treatment. In this case, the rootstockseedling was grafted to a cucurbit scion at about 24 hours after therootstock shoot apical meristem was first contacted with the fattyalcohol composition.

Example 2 Preparation of a Grafted Cucurbit Plant (Species Here) Using aCucurbit Rootstock Plant from Example 1

Grafting can be performed at about 1-21 days after a rootstock shootapical meristem is treated with a fatty alcohol solution. Possiblegrafting methods include the following: 1) hole-insertion, in which therootstock meristem is removed, a hole is punched into the oldmeristematic area with a bamboo needle, and the scion (cut at the end toboth sharpen and expose vascular cambium tissue) is inserted into theprepared rootstock; and 2) one cotyledon, where the rootstock's meristemarea and one cotyledon are removed, and the cut scion hypocotyl isadjoined to the resulting wound, stabilized with a clip, and allowed toheal. Once grafted, the plants are placed for approximately seven daysin a healing chamber under high humidity for about the first 1-3 days,and then gradually decreasing humidity for the remaining days. Afterabout seven days of healing, the grafted plants can be removed from thechamber and planted.

In this case, the cucurbit rootstock seedling as described in Example 1was grafted to a cucurbit scion, watermelon (Citrullus lanatus subsp.vulgaris cv. ‘Tri-X-313’) or melon (Cucumis melo cv. ‘Athena’) at about24 hours after the rootstock shoot apical meristem was first contactedwith the fatty alcohol composition. Seven days were allowed for thegraft to heal. Out of a total of 2016 grafts performed over 1800(90-100%) were successful and all exhibited death of the rootstockmeristem.

Example 3 Results of Treating Cucurbit Rootstock Apical Shoot MeristemsUsing Maleic Hydrazide, Sulphuric Acid or Oryzalin Chemical Means Otherthan Fatty Alcohol Compositions

The same rootstock and scion species were used in this example as inExamples 1 and 2.

Maleic hydrazide. Maleic hydrazide (21.7%; Royal MH-30®; Chemtura Corp.,Middlebury, Conn.) at a concentration of about 90 mg/ml was applied tothe shoot apical meristem of rootstock plant. The treated rootstockplants were incubated for about 24 hours prior to grafting to a scion.

Similar to fatty alcohols solutions, maleic hydrazide solutions are usedto inhibit tobacco sucker growth. However, in the case of the inhibitionof shoot meristem growth in cucurbit rootstock plants, maleic hydrazidewas found not only to inhibit apical meristem growth but it was alsofound to inhibit grafting as no grafts were successful when maleichydrazide was used. Thus, out of 2016 attempted grafts, 100% inhibitionof meristematic growth was observed but no successful grafts wereobserved.

Oryzalin. Oryzalin or Surflan AS (Dow AgroSciences), a herbicide forannual grasses and broadleaf weeds, was applied to the shoot apicalmeristem of the cucurbit rootstock plant at a concentration of about 10times the rate suggested on the label (i.e., about 10 mM). The treatedrootstock plants were incubated with the Oryzalin for about 24 hoursprior to grafting. Out of 2016 attempted grafts, over 1800 of the graftswere successful (90-100%). However, even at rates of up to 10× therecommended amount, Oryzalin was only able to stunt but not stop theapical meristem from growing. Thus, zero percent meristem inhibition wasobserved.

Sulfuric acid. Sulfuric acid at a concentration of about 18N to about 9Nwas applied to the shoot apical meristem of the cucurbit rootstockplant. The treated rootstock plants were incubated with the sulfuricacid for about 24 hours prior to grafting. Application of sulfuric acidresulted in death of the shoot apical meristem but in addition, thegrafting tissues were also destroyed. Thus, out of 2016 attempted graftsnone were successful.

Example 4 Fatty Alcohol Treatment to Increase Total Non-StructuralCarbohydrates in Cucurbit Rootstock

After treatment with fatty alcohols (“blinding”), it was observed thatrootstocks increase in size and the hypocotyls and cotyledons becomelonger and thicker. Thus, in addition to removing the meristem andpreventing rootstock regrowth, chemical decapitation of the rootstockusing fatty alcohol treatment as described above may allow the rootstockto store more carbohydrates in the hypocotyl, thus resulting in anincreased graft success rate.

To quantify these observations, seedlings of bottle gourd (e.g.,‘Emphasis’ bottle gourd; Syngenta Seeds, Boise Id.) and interspecifichybrid squash (e.g., ‘Carnivor’ Interspecific Hybrid Squash) wereplanted in 72-cell trays (72 plants per treatment) and treated with adilute fatty alcohol solution (6.25% Fair 85; Fair Chemicals, Inc.) atthe point when the cotyledons first unfolded (about 6-10 days afterplanting). Seedlings were harvested on 1, 7, 14, and 21 days posttreatment. Hypocotyls and cotyledons were harvested and the followingmeasurements were taken: fresh weight, dry weight, length, width, andcotyledon area. Leaf Thickness was estimated according to the followingformula (Vile et al. Annals of Botany 96: 1129-1136 (2005)):(SLA×LDMC)⁻¹, wherein SLA=Specific Leaf Area (leaf area/leaf dry mass)and LDMC=Leaf Dry Matter Content (leaf dry mass/fresh mass).

To determine the total nonstructural carbohydrate content, tissue wasdried in an oven at 50° C. for 72 hours and hypocotyl and cotyledon dryweights were taken. The dried hypocotyls or cotyledons of five plantswere combined, ground, and frozen until assayed. Seventy mg of tissuewas used to assay for total nonstructural carbohydrates (TNC) accordingto the protocol of Zhao et al. (Crop Science 50:1537-1545 (2010)). Inbrief, Glucose, Sucrose, and Fructose were purified via an 80% ethanolextraction and activated charcoal filtration. Fructan was extracted fromthe ethanol-soluble solution via an acid digest in 0.2 M acetic acid.Following ethanol extraction, starch was enzymatically extracted fromthe original sample residue and separated into glucose units. Fructose,sucrose, and fructan were enzymatically converted to glucose and Glucose(HK) Assay Kit (GAHK) reagent (includes enzymes and other reagents usedto determine the concentrations of glucose) was added and absorbance at340 nm was measured. Concentrations were determined by use of a standardcurve, sugar amount per gram hypocotyl was calculated using the dryweight of the tissue, and average hypocotyl weight was used to calculatethe amount of TNC per hypocotyl. The controls were plants were seedlingsharvested on day one.

The results are shown in Tables 1-5 and FIGS. 3-15.

TABLE 1 Amount of glucose per hypocotyl versus cotyledon. ug Glucose perg dried tissue Carnivor Emphasis Hypocotyl Cotyedon Hypocotyl CotyledonDay Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2  1 0.21 0.59 0.1 0.70.21 0.34 0.05 0.24  7 0.31 1.44 0.99 2.06 0.43 0.64 0.55 1.26 14 1.962.12 1.08 1.36 0.87 0.74 0.78 1.22 21 2.71 2.11 0.99 1.1 0.98 0.86 0.991.05 Increase 13.21 3.6 10.54 2.95 4.66 2.55 19.3 5.35 Difference 2.51.52 0.98 1.36 0.77 0.52 0.93 1.03

TABLE 2 Amount of sucrose per hypocotyl versus cotyledon. ug Sucrose perg dried tissue Carnivor Emphasis Hypocotyl Cotyedon Hypocotyl CotyedonDay Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2  1 0.18 0.30 0.050.99 0.07 0.05 0.08 0.32  7 0.19 0.29 0.36 1.12 0.1 0.07 0.12 0.51 140.47 0.56 0.89 1.89 0.21 0.31 0.35 1.14 21 0.64 0.54 1.11 2.47 0.47 0.210.52 1.24 Increase 3.55 1.84 20.38 2.5 6.73 5.8 6.8 3.87 Difference 0.460.25 1.05 1.48 0.4 0.25 0.44 0.92

TABLE 3 Amount of fructose per hypocotyl versus cotyledon. ug Fructoseper g dried tissue Carnivor Emphasis Hypocotyl Cotyledon HypocotylCotyledon Day Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2  1 0.280.44 0.18 0.38 0.11 0.2 0.04 0.11  7 0.33 0.65 0.92 0.75 0.21 0.31 0.380.55 14 0.7 1.01 1.06 0.74 0.35 0.45 0.49 0.55 21 0.87 1.13 0.77 0.520.56 0.5 0.49 0.6 Increase 3.12 2.55 6.18 1.98 3.17 2.55 13.06 5.34Difference 0.59 0.69 0.89 0.37 0.29 0.3 0.45 0.49

TABLE 4 Amount of starch per hypocotyl versus cotyledon. ug Starch per gdried tissue Carnivor Emphasis Hypocotyl Cotyledon Hypocotyl CotyledonDay Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2 Rep 1 Rep 2  1 0.05 0.07 −0.0020.16 0.01 0.03 0.005 0.08  7 1.21 3.67 1.52 2.92 0.07 0.29 1.13 2.08 144.37 5.44 2.74 3.2 0.24 0.7 2.025 2.52 21 7.33 8.15 4.25 4.03 0.41 1.042.91 4.07 Increase 153.11 111.4 2.8 25.28 37.31 36.3 540.68 50.48Difference 7.28 8.08 4.25 3.87 0.4 1.01 2.9 3.99

TABLE 5 Amount of total nonstructural carbohydrate per hypocotyl versuscotyledon. ug TNC components per g dried tissue Carnivor EmphasisHypocotyl Cotyledon Hypocotyl Cotyledon Day Rep 1 Rep 2 Rep 1 Rep 2 Rep1 Rep 2 Rep 1 Rep 2  1 0.64 1.4 0.33 2.23 0.4 0.61 0.17 0.75  7 2.036.04 3.79 6.85 0.75 1.29 2.09 4.41 14 6.4 9.12 5.78 7.18 1.67 2.2 3.635.42 21 9.72 11.92 7.12 8.12 2.43 2.61 4.9 6.96 Increase 15.04 8.4921.74 3.65 6.09 4.25 28.81 9.27 Difference 9.08 10.52 6.79 5.89 2.02 24.73 6.21

Each table contains the results from two planting dates. In each case,date 1 (6 Aug. 2012) is shown in the first column (Rep 1) and date 2 (17Sep. 2012) is shown in the second column (Rep 2). The row labeled“Increase” shows the result of the highest result/lowest result to givean idea of the multiplicity of the increase. The row labeled“Difference” illustrates the difference between the highestconcentration and Day 1. Any negative values were calculated as zero.Tables 1-3 show ethanol-soluble sugars. The results were negative forfructan, which is not a sugar produced by cucurbits (data not shown).Table 4 shows the results for starch, which shows the greatest increase.Table 5 shows the sum of sugars and starch multiplied by the averagehypocotyl or cotyledon weight to illustrate the amount of sugaravailable in the average hypocotyl or cotyledon. A significant increaseis evident for all treatments.

As can be seen in FIGS. 3-12, both cotyledon and hypocotyl sizes (lengthand width) as well as fresh and dry weights increased as a result of thetreatment with the fatty alcohols in both bottle gourd and interspecifichybrid squash rootstocks.

Rep 1 data from Tables 1-5 are shown in FIGS. 13-15. FIG. 13 and FIG. 14illustrate the raw concentration of four TNC (glucose, fructose,sucrose, and starch) observed in the plant hypocotyls over time. Asnoted above, the results for fructans are not shown, as the analysisyielded no result. A significant increase in μg glucose per gram tissueover time is seen for both bottle gourd and interspecific hybridrootstocks, with the peak glucose concentration occurring on day 14following fatty alcohol treatment. This increase is more significant inthe interspecific hybrid than in the bottle gourd. Although sucroselevels decrease on day seven, no significant increase or decrease overtime is shown in fructose or sucrose per gram tissue. As shown in FIG.14, of the TNC components analyzed, starch concentration (μg starch/gtissue) increases most significantly.

FIG. 15 combines the TNC concentrations (FIGS. 13 and 14) with theaverage hypocotyl dry weight (FIG. 4) to illustrate the observedincrease in average amount of TNC per hypocotyl. Each TNC componentshows a significant increase over the 21-day testing period, with theinterspecific hybrid rootstock showing a greater increase than thebottle gourd. Of the nonstructural carbohydrates, the amount of glucoseand starch increased the most dramatically. The increase observed intotal nonstructural carbohydrate, as well as the increase observed inrootstock seedling size, illustrates the effectiveness of the use offatty alcohols for not only removing the meristem and preventingrootstock regrowth, but also for allowing the rootstock seedlings tostore more carbohydrates in the hypocotyl, which can lead to anincreased graft success rate.

The foregoing is illustrative of the present invention, and is not to beconstrued as limiting thereof. The invention is defined by the followingclaims, with equivalents of the claims to be included therein.

All publications, patent applications, patents and other referencescited herein are incorporated by reference in their entireties for theteachings relevant to the sentence and/or paragraph in which thereference is presented.

1-30. (canceled)
 31. A cucurbit rootstock plant produced by (a)contacting a shoot apical meristem of the cucurbit plant with aneffective amount of a composition comprising one or more fatty alcoholsduring the time period from when the cucurbit plant's cotyledons openuntil the appearance of the first true leaf, thereby inhibiting thegrowth of the shoot apical meristem of the cucurbit plant and (b)producing said curcurbit rootstock plant.
 32. A grafted cucurbit plantproduced by (a) contacting a shoot apical meristem of a cucurbitrootstock plant with an effective amount of a composition comprising oneor more fatty alcohols prior to grafting; and (b) grafting a cucurbitscion onto the cucurbit rootstock plant of (a).
 33. The cucurbitrootstock plant of claim 31, wherein at least one nonstructuralcarbohydrate is increased in said cucurbit rootstock plant.
 34. Thegrafted cucurbit plant of claim 32, wherein at least one nonstructuralcarbohydrate is increased in said grafted cucurbit plant.
 35. Thecucurbit rootstock plant of claim 31, wherein the composition comprisesN-hexanol fatty alcohol (C₆), N-octanol (C₈) fatty alcohol, N-decanol(C₁₀) fatty alcohol, N-dodecanol (C₁₂), N-tetradecanol, or anycombination thereof.
 36. The grafted cucurbit plant of claim 32, whereinthe composition comprises N-hexanol fatty alcohol (C₆), N-octanol (C₈)fatty alcohol, N-decanol (C₁₀) fatty alcohol, N-dodecanol (C₁₂),N-tetradecanol, or any combination thereof.
 37. The cucurbit rootstockplant of claim 31, wherein the composition comprises N-octanol (C₈)fatty alcohol and/or N-decanol (C₁₀) fatty alcohol.
 38. The graftedcucurbit plant of claim 32, wherein the composition comprises N-octanol(C₈) fatty alcohol and/or N-decanol (C₁₀) fatty alcohol.
 39. Thecucurbit rootstock plant of claim 35, wherein the composition comprisingone or more fatty alcohols comprises FAIR 85®, Offshoot-T®, SuckerPlucker®, or any combination thereof.
 40. The grafted cucurbit plant ofclaim 36, wherein the composition comprising one or more fatty alcoholscomprises FAIR 85®, Offshoot-T®, Sucker Plucker®, or any combinationthereof.
 41. The cucurbit rootstock plant of claim 31, wherein thecomposition comprises a concentration of 2% (volume/volume) to about 40%(volume/volume) of fatty alcohols or about 2% (volume/volume) to about20% (volume/volume) of fatty alcohols.
 42. The grafted cucurbit plant ofclaim 32, wherein the composition comprises a concentration of 2%(volume/volume) to about 40% (volume/volume) of fatty alcohols or about2% (volume/volume) to about 20% (volume/volume) of fatty alcohols. 43.The cucurbit rootstock plant of claim 31, wherein the cucurbit plant isa wild watermelon rootstock plant, a bottle gourd rootstock plant, aninterspecific squash rootstock plant, figleaf gourd, wax gourd, C.moschata, Cucumis hystrix Chakrav. Cucumis hytivus J. F. Chen & J. H.Kirkbr., Cucumis metuliferus E. Mey ex Naud, Cucumis melo, and/or otherwild-type cucurbit.
 44. The grafted cucurbit plant of claim 32, whereinthe cucurbit rootstock plant is a wild watermelon rootstock plant, abottle gourd rootstock plant, an interspecific squash rootstock plant,figleaf gourd, wax gourd, C. moschata, Cucumis hystrix Chakrav. Cucumishytivus J. F. Chen & J. H. Kirkbr., Cucumis metuliferus E. Mey ex Naud,Cucumis melo, and/or other wild-type cucurbit.
 45. The cucurbitrootstock plant of claim 43, wherein the bottle gourd rootstock plant isLagenaria spp. or Lagenaria siceraria, the interspecific squashrootstock plant is Cucurbita maxima×Cucurbita moschata, the figleafgourd is Cucurbita ficifolia, the wax gourd is Benincasa hispida and thewild-type cucurbit is C. lanatus, Citrulus lanatus subsp. lanatus‘Ojakkyo’, Citrullus lanatus subsp. mucosospermus, Cucumis africanus, orCucumis myriocarpus.
 46. The grafted cucurbit plant of claim 44, whereinthe bottle gourd rootstock plant is Lagenaria spp. or Lagenariasiceraria, the interspecific squash rootstock plant is Cucurbitamaxima×Cucurbita moschata, the figleaf gourd is Cucurbita ficifolia, thewax gourd is Benincasa hispida and the wild-type cucurbit is C. lanatus,Citrulus lanatus subsp. lanatus ‘Ojakkyo’, Citrullus lanatus subsp.mucosospermus, Cucumis africanus, or Cucumis myriocarpus.
 47. Thegrafted cucurbit plant of claim 32, wherein the cucurbit scion is awatermelon plant (Citrullus lanatus subsp. lanatus or Citrullus lanatussubsp. mucosospermus), a melon plant (Cucumis melo), an oriental melonplant (Cucumis melo var. makuwa) or a cucumber plant (Cucumis sativus).48. A method of increasing the grafting success rate between a cucurbitrootstock plant and a cucurbit scion plant, comprising grafting acucurbit scion onto the cucurbit rootstock plant of claim 31, whereinthe grafting success rate of the rootstock to the scion is increased.49. The method of 48, wherein the rootstock plant is a wild watermelonrootstock plant, a bottle gourd rootstock plant, an interspecific squashrootstock plant, figleaf gourd, wax gourd, C. moschata, Cucumis hystrixChakrav. Cucumis hytivus J. F. Chen & J. H. Kirkbr., Cucumis metuliferusE. Mev. ex Naud., Cucumis melo, and/or other wild-type cucurbit.
 50. Themethod of claim 49, wherein the bottle gourd rootstock plant isLagenaria spp. or Lagenaria siceraria, the interspecific squashrootstock plant is Cucurbita maxima×Cucurbita moschata, the figleafgourd is Cucurbita ficifolia, the wax gourd is Benincasa hispida and thewild-type cucurbit is C. lanatus, Citrulus lanatus subsp. lanatus‘Ojakkyo’, Citrullus lanatus subsp. mucosospermus, Cucumis africanus, orCucumis myriocarpus.
 51. The method of claim 48, wherein the cucurbitrootstock is a bottle gourd plant and the scion is a watermelon plant(Citrullus lanatus subsp. lanatus); the cucurbit rootstock plant is aninterspecific squash rootstock plant and the scion is a watermelon plant(Citrullus lanatus subsp. lanatus or Citrullus lanatus subsp.mucosospermus), a melon plant (Cucumis melo), an oriental melon plant(Cucumis melo var. makuwa) or a cucumber plant (Cucumis sativus); thecucurbit rootstock plant is a figleaf gourd plant and the scion is acucumber plant; the cucurbit rootstock plant is Cucurbita moschata andthe scion is a cucumber plant or a watermelon plant; the cucurbitrootstock plant is wild watermelon (Citrullus lanatus subsp. lanatus orCitrullus lanatus subsp. mucosospermus) and the scion is a watermelonplant; the cucurbit rootstock plant is Cucumis melo var. makuwa and thescion is a melon plant; or the cucurbit rootstock plant is wax gourd andthe scion is a watermelon plant.